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Some of the most common mental disorders, including depression, anxiety and PTSD, might not be disorders at all, according to a recent paper by Washington State University biological anthropologists.

In the paper, published in the Yearbook of Physical Anthropology, the researchers propose a new approach to mental illness that would be informed by human evolution, noting that modern psychology, and in particular its use of drugs like antidepressants, has largely failed to reduce the prevalence of mental disorders. (This paper was made available online on Nov. 28, 2019 ahead of final publication in the issue on April 28, 2020). For example, the global prevalence of major depressive disorder and anxiety disorders remained steady at 4.4% and 4% respectively from 1990 to 2010.

The authors also theorize that depression, anxiety and post-traumatic stress disorder may be primarily responses to adversity; therefore, only treating the “psychic pain” of these issues with drugs will not solve the underlying problem. Kristen Syme, the first author on the paper and recent WSU Ph.D. graduate, compared it to medicating someone for a broken bone without setting the bone itself.

“The pain is not the disease; the pain is the function that is telling you there is a problem,” said Syme. “Depression, anxiety and PTSD often involve a threat or exposure to violence, which are predictable sources for these things that we call mental diseases. Instead, they look more like sociocultural phenomena, so the solution is not necessarily fixing a dysfunction in the person’s brain but fixing dysfunctions in the social world.”

Syme and co-author Edward Hagen advocate for biological anthropologists to enter the study of the “diseases of the mind,” to help find effective solutions, particularly for some problems that may be social instead of mental.

“Mental health research is still very much stuck in a view that comes out of the 19th century, and revived in 1980, of classifying everything by symptoms in the hopes of revealing underlying patterns that would lead to solutions, but it really has not,” said Hagen, a WSU professor of evolutionary anthropology and corresponding author on the paper. “Even though we’re using new measurements, like genetics, biomarkers and imaging, these still haven’t added up to the insights needed to really improve people’s lives.”

Among the more problematic issues, the researchers point to the “chemical imbalance” theory of depression, which has helped create a boom in antidepressant drugs meant to modulate certain chemicals in the brain called neurotransmitters. A large meta-analysis of antidepressant trials in 2018 found that antidepressants had almost the same effect as a placebo, and their widespread use has not delivered measurable results. For example, in Australia alone, antidepressant use increased 352% from 1990 to 2002, yet there has been no observed reduction in the prevalence of mood, anxiety or substance use disorders in any country.

Instead of addressing mental issues by their symptoms, Hagen and Syme propose approaching mental illness by their probable causes. They acknowledge that some psychiatric disorders like schizophrenia are likely genetic and often inherited and others like Alzheimer’s appear connected with aging.

However, the anthropologists argue that some conditions might be a mismatch between modern and ancestral environments such as attention-deficit/hyperactivity disorder, also known as ADHD. Hagen pointed out that there is little in our evolutionary history that accounts for children sitting at desks quietly while watching a teacher do math equations at a board.

Other disorders such as depression, anxiety and PTSD are not hereditary, occur at any age and are often tied to threatening experiences. Hagen and Syme propose they may be responses to adversity and serve as signals, much like physical pain does, to make people aware of the need for help.

These conditions also disproportionately affect people in developing countries. For instance, 1 in 5 people in conflict-affected countries suffer from depression versus 1 in 14 in worldwide.

“As anthropologists, we should be studying this a lot more because the mental health burden in the populations we often study is quite high,” Hagen said. “In many cases, they’re suffering from pervasive warfare, conflict and inadequate policing.”

Yale researchers have found a neural home of the feeling of stress people experience, an insight that may help people deal with the debilitating sense of fear and anxiety that stress can evoke, Yale researchers report May 27 in the journal Nature Communications.

Brain scans of people exposed to highly stressful and troubling images — such as a snarling dog, mutilated faces or filthy toilets — reveal a network of neural connections emanating throughout the brain from the hippocampus, an area of the brain that helps regulate motivation, emotion and memory.

The brain networks that support the physiological response to stress have been well studied in animals. Activation of brain areas such as the hypothalamus triggers production of steroid hormones called glucocorticoids in the face of stress and threats. But the source of the subjective experience of stress experienced by people during the COVID-19 pandemic, for instance, has been more difficult to pinpoint.

“We can’t ask rats how they are feeling,” said Elizabeth Goldfarb, associate research scientist at the Yale Stress Center and lead author of the study.

Goldfarb and co-authors, including senior author Rajita Sinha, the Foundations Fund Professor of Psychiatry, conducted a series of fMRI scans of subjects who were asked to quantify their stress levels when presented with troubling images.

The study reveals that neural connections emanating from the hippocampus when viewing these images reached not only areas of the brain associated with physiological stress responses, but also the dorsal lateral frontal cortex, an area of the brain involved in higher cognitive functions and regulation of emotions. The Yale team found that when neural connections between the hippocampus and frontal cortex were stronger, subjects reported feeling less stressed by the troublesome images.

Conversely, subjects reported feeling more stressed when the neural network between the hippocampus and hypothalamus was more active.

The authors note there is also evidence from other studies that those suffering from mental health disorders such as anxiety may have difficulty receiving calming feedback from the frontal cortex in times of stress.

“These findings may help us tailor therapeutic intervention to multiple targets, such as increasing the strength of the connections from the hippocampus to the frontal cortex or decreasing the signaling to the physiological stress centers,” said Sinha, who is also a professor in Yale’s Child Study Center and neuroscience department.

All study subjects were healthy, she said, and in some cases their responses during the experiment seemed to be adaptive — in other words, the network connections with the frontal cortex became stronger as the subjects were exposed to the stressful images. Sinha and Goldfarb speculated that these subjects might be accessing memories that help moderate their response to stressful images.

“Similar to recent findings that remembering positive experiences can lower the body’s stress response, our work suggests that memory-related brain networks can be harnessed to create a more resilient emotional response to stress,” Goldfarb said.

Fatty food may feel like a friend during these troubled times, but new research suggests that eating just one meal high in saturated fat can hinder our ability to concentrate — not great news for people whose diets have gone south while they’re working at home during the COVID-19 pandemic.

We may like to assume that we are adults when we turn eighteen; however, the truth is our brain is still undergoing a significant amount of construction until our mid-twenties. Research has shown that the brain is not fully developed until a person reaches about the age of twenty-five. For males, full development can extend until the age of twenty-eight. What does this mean for you? If you are under twenty-five, this means every decision you make, every thought you have, every action you take, all the food you eat, the amount of sleep you get and everything else you do throughout your day has significant impact on your developing brain.

Sleep patterns around the world have been disrupted as screen time increases and sleep routines change with COVID-19 self-isolation requirements. Negative mood is not unusual in adolescence, but lack of sleep can affect mental health, causing anhedonia (or loss of pleasure), anxiety, anger and significantly increasing the risk of depression, a global study of more than 350,000 teens shows.

Sleep patterns around the world have been disrupted as screen time increases and sleep routines change with COVID-19 self-isolation requirements.

Negative mood is not unusual in adolescence, but lack of sleep can affect mental health, causing anhedonia (or loss of pleasure), anxiety, anger and significantly increasing the risk of depression, a global study of more than 350,000 teens shows.

The results just published in Sleep Medicine Reviews connects less sleep with a 55% increased chance of mood deficits and double the risk of reduced positive mood.

World-first research led by neuroimaging expert Dr. Jiyang Jiang at UNSW’s Centre for Healthy Brain Ageing (CHeBA) has found that those aged 95 and over demonstrated more activation between the left and ride side of their brain than their younger counterparts.

Given the prevalence of dementia increases with age, near-centenarians and centenarians without dementia are generally considered as models of successful aging and resistance against age-related cognitive decline.

“We wanted to see if there was something particularly special about the brain‘s functional connectivity of those aged 95 and older that helps them preserve brain function into the 11th decade of their life,” says Dr. Jiang.